Process of producing cocoa shell powder

ABSTRACT

A process for producing powdered cocoa shells as a food ingredient, as replacer for cocoa powder, to impart coloration in food products, and as fat bloom inhibitor in cocoa-based products.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 15/008,407, filed on Jan. 27, 2016, which is a continuation of U.S.application Ser. No. 13/927,586, filed on Jun. 26, 2013, which is acontinuation-in-part of PCT/CH2012/000277, filed Dec. 20, 2012, whichclaims the benefit of GB1122368.2, filed Dec. 23, 2011, and GB1205847.5, filed Mar. 30, 2012, the contents of each of which are hereinincorporated by reference in their entireties.

FIELD OF THE INVENTION

This invention relates to a process for producing cocoa shell powder, inparticular to cocoa shell powder depleted in heavy metals, to the use ofcocoa shell powder processed thereby as a food ingredient or as replacerfor cocoa powder in chocolate, fillings, beverages, compounds, vendingmixes or as such, to the use of this cocoa shell powder to impartcolouration in food products, to the use of this cocoa shell powder inorder to make chocolate products more resistant against fat bloom, andto food products containing cocoa shell powder as described above.

BACKGROUND OF THE INVENTION

Cocoa beans in their shells are conventionally processed at elevatedtemperatures until the shell detaches from the nibs. The shells are thencracked and separated from the nibs which are further processed invarious ways to produce cocoa powder and chocolate products (see Fincke,H. “Handbuch der Kakaoerzeugnisse”, 2. Auflage 1965). The shells areconsidered as waste by-products for which several applications have beenfound.

US2011/0151098 provides a food comprising at least 30 mass % alkalizedcocoa shells in the food and a method for manufacturing thecorresponding food. However, this method does not comprise any washingsteps or any removal of heavy metals.

EP2174555 discloses an acidified dairy food comprising cocoa shells, amethod for its production, and the use of cocoa shells to increase thefibre content and/or the lower fat content of an acidified dairyproduct.

In United Kingdom patent application 2452972 a chocolate is describedwhich incorporates cocoa beans with or without their shells.

EP1728434 discloses a process for extracting cocoa shells in order toproduce fractions enriched in theobromine or in polyphenols.

European patent 1733624 relates to a process for milling cocoa shellswithout moving mechanical parts and to the granular edible productsthereof. However, this invention as claimed performs a mere dryprocessing of cocoa shells and does not refer to any washing procedureor measures which are targeted on reducing the heavy metal concentrationin cocoa shells.

Spanish patent ES 2099676 discloses a cocoa fibre product based onroasted cocoa husks and its application as a dietetic product in thepharmaceutical and food industry. However, no process parameters such aswashing steps are mentioned.

GB patent 1195634 claims a flavouring and colouring extract from cocoashells for use in confectionery and ice cream products.

In U.S. Pat. No. 4,156,030 there is a process described for preparing aberry-like flavourant and colorant by extracting cocoa shells with anacidified ethanol solution and by separating the resulting extract fromthe cocoa shell residue.

Furthermore, cocoa shells can be used inter alia for manufacturing paper(see http://www.blackmountainchocolate.com), for mulching (seewww.ag-choice.com), for the manufacture of plastic products (seeEP0784081A1) or of meat food packaging (see JP55064781A), as substitutefor cork in linoleum (see Greenwood-Barton, L. H. Food Manufacture 1965;May: 52-56) or for cosmetics (see http://www.saag-ge.ch).

In the field of engineering sciences, several publications describe theuse of cocoa shells as biofiltration support and for the removal ofmetals from contaminated soil and industrial effluents (see Meunier, N.et al. Bioresource Technology 2003; 90: 255-263).

For several decades it has been known that cocoa shells may containundesirable components such as mycotoxins, heavy metals or pesticideswhich often pose a risk to human health (see “10 Jahre Katrin Janßen imLCI: Kakaoschalenforschung und Qualitätsmanagement”. Süsswaren 2009;11-12). The majority of ochratoxin A in cocoa beans, e.g., is present inthe cocoa shells and 98% of initial ochratoxin A contamination fromcocoa beans can be removed by applying bicarbonate washing (seeAmezqueta, S. et al. Alimentacion Equipos y Tecnologia 2009; 240:38-42). Furthermore, due to their strong ion exchange properties cocoashells significantly accumulate toxicologically relevant metal speciessuch as aluminium (Al), lead (Pb), cadmium (Cd), chromium (Cr), cobalt(Co), iron (Fe) and nickel (Ni). Especially cocoa shells processed fromcocoa beans of South American or Caribbean origin are remarkablycontaminated by cadmium (see Matissek, R. und M. Raters. “Toxikologischrelevante Elemente in Kakao—Vorkommen und Risikobewertung”. Projekt Nr.55. Stiftung der Deutschen Schokoladen- und Kakaowirtschaft. 2008).

Differently coloured cocoa-based food products may be prepared byalkalizing cocoa nibs, cocoa liquor or cocoa cake and cocoa powder,respectively. Whereas liquor alkalization potentially leads todegradation of cocoa butter and results in a narrow range of colour andflavour profiles, the alkalization of cocoa cake or cocoa powder may beaccompanied by protein and starch degradation providing unfavourableeffects on texture and taste of dairy food and confectionery. Althoughnib alkalization is regarded as best option for colour and flavourdevelopment in cocoa-based products, this process is more complex andcost-intensive due to the high commodity value of cocoa butter (seeDyer, B. 57th PCMA Production Conference 2003; 130-131; see Fischer, J.The Manufacturing Confectioner 2009; September: 89).

Alternatively, alkalized cocoa shell powder may be used to impartcolouration in food products. Since cocoa shells on average contain onlyabout 4 weight % of fatty components, the disadvantages associated withdecomposition of cocoa butter can be avoided. EP2174557 discloses a foodcomprising at least 30 mass % alkalized cocoa shells as the only sourceof chocolate flavour in food products. However, this patent applicationis silent on processing of cocoa shells comprising the steps of sieving,grinding, washing, alkalizing and heavy metal removal.

Fat bloom in chocolate products is a major problem in the chocolateindustry. “Bloom” in this context means a separation of fat crystalsfrom the matrix of the chocolate, generally caused by separation ofcocoa butter from the matrix and extrusion or recrystallization of fatto or on the surface with the result being white layering or splotcheson the surface of the chocolate. Bloom is usually ascribed to partialliquification, e.g. due to temperature fluctuations, and thenrecrystallization of the fat which sometimes migrates to the surface.The bloom appears as a white, waxy substance on the surface of thechocolate and is objectionable to consumers.

Document JP2006271328A discloses an oil and fat composition containing afat bloom preventing agent to be used for chocolate manufacture. The fatbloom preventing agent is selected from the group consisting of glycerolorganic acid fatty acid ester, polyglyceryl saturated fatty acid ester,and sorbitan saturated fatty acid ester.

Japanese patent 2138937 claims a composition which can prevent fat bloomby using more than 20 weight % of a specific monounsaturated anddisaturated triglyceride in which more than 75 weight % of the saturatedgroups is the residue of stearic acid.

U.S. Pat. No. 5,849,353 provides a process for preventing fat bloom in achocolate-like product containing non-tempering cocoa butter substitute.

Chocolate fat bloom caused by a Form V to a Form VI transformation,whether or not this is also linked to fat migration, can be inhibited bythe use of fats called “Prestine” with a very specific triglyceridecomposition (see Talbot, G. IFI 1995; 1: 40-45).

SUMMARY OF THE INVENTION

The present applicants have sought to find an economically improvedmethod for processing cocoa shells and to use these processed cocoashells as fat bloom inhibitor, as a food ingredient in dairy products,as volume replacer for cocoa powder in chocolate, filings, beveragescompounds, vending mixes or as such and to impart colouration in foodproducts.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1. Depicts a cone biscuit as described in Example 5.

DESCRIPTION OF THE INVENTION

In one aspect, therefore, this invention provides a process forproducing cocoa shell powder from preroasted cocoa beans. The cocoabeans may be of African, Asian, Central American or South Americanorigin and may be unfermented, fermented or well-fermented. The firstprocess steps comprising preroasting, cracking, removing and separatingthe cocoa shells from the nibs as well as selecting and separating afraction of cocoa shells, e.g. by sieving, may be done by standardprocesses, as described inter alia in Fincke, H., “Handbuch derKakaoerzeugnisse”, 2. Auflage 1965. Alternatively, the G. W. Barth NARS(Nibs, Alkalization and Roasting System) process may be applied,characterized by a careful treatment of the raw beans. Exposure ofcleaned beans to infrared radiation enables optimal shell detachment(http://www.buhlergroup.com).

Suitable fractions of cocoa shells resulting from a winnowing process(Z10 (>2.8 mm) up to Z1 (>7 mm)) may be selected according to their meanparticle size of more than 1 mm, e.g. of 2.8 mm. Fractions characterizedby a mean particle size of less than 1 mm contain higher amounts ofcontaminants such as dust and sand and may be discarded.

A grinding step enhancing the washing efficiency may be inserted betweenselecting and washing of cocoa shells. This procedure performed by acentrifugal breaker system increases the density of cocoa shells fromabout 175 g/L for particles larger than 2.8 mm to about 275 g/L forparticles of a mean size of 3.8 mm, whose diameter does not exceed 5 mm.

In order to remove sand, off-flavour notes and undesired components suchas mycotoxins or pesticides, the selected fractions may be washed byaqueous buffer solutions based on weak inorganic or organic acids andtheir conjugated bases or on weak inorganic or organic bases and theirconjugated acids, adjusted to a pH value between 2.0 and 9.0, e.g. 4.0to 7.0, e.g. about 7.0. The washing temperature applied may be between15° C. and 100° C., e.g. 80° C. Selected fractions of cocoa shells maybe submerged in the buffer solution, whose weight exceeds the weight ofthe cocoa shells by a factor of 0.5 to 30, and may be agitated for aperiod of time between 1 min and 12 h. This washing step may be repeatedup to five times. After the buffer solution has finally been drained,the wet cocoa shells may be dried by heat convection, heat conduction,steam and vacuum or counter current heated air, applied for up to 24 hat a temperature higher than 50° C. to a moisture content less than 10weight %, e.g. less than 5 weight %.

After the washing step using aqueous buffer solutions or alternativelyafter the final drying and grinding steps, the selected fractions ofcocoa shells may be alkalized by standard processes, e.g. as describedin Fincke, H., “Handbuch der Kakaoerzeugnisse”, 2. Auflage 1965. Bymeans of alkalization of cocoa nibs and depending on the processparameters and the alkaline components used, colours may be achievedranging from brown over red to black cocoa powder. Process conditionsfor manufacturing black cocoa powder as reference have been developedand a colour specification is set for external colour values, as givenin Table 2. Alkalization of cocoa shells may be performed by suspendingwashed cocoa shells in 9 to 14 weight % water, by adding 1.5 to 7 weight% of an aqueous solution (concentration: 100% w/w) of an alkali metalcarbonate such as potassium carbonate, and by adding 15 to 25 weight %of an aqueous solution (concentration: 25% w/w) of an alkali metalhydroxide such as sodium hydroxide. Either or both alkaline solution maybe applied. Optionally, 0.008 to 0.009 weight % of an iron componentsuch as iron(III)sulfate, iron(III)chloride, iron(III)citrate,iron(III)glycerol-phosphate or iron saccharate may be added to thealkalization batch. All details on weight percentage given above referto the initial weight of washed and dried cocoa shells. The alkalizationprocedure may be performed at a temperature between 80 and 130° C., e.g.95° C. or 125° C., for a period of time of 20 to 85 min, e.g. 60 min,and at a pressure between 2 and 8 bar, e.g. 5 bar. Finally, thealkalized cocoa shell powder may be cooled to a temperature of about 60to 70° C., e.g. 65° C., in 7 to 12 min and dried for a period of time of35 to 85 min before being ground to a mean particle size of less than 75μm.

In order to reduce the concentration of metal contaminants in cocoashells as described above, the washed cocoa shell may be treated with achelating agent which comprises an organic acid or any alkali metal saltor alkali earth metal salt thereof as chelating agents. This organicacid may contain at least two carboxylic groups, e.g. tartaric acid,preferably three carboxylic groups, e.g. citric acid. The chelatingagent may be applied in aqueous solution at a concentration of 1 mM to 5M, e.g. about 100 mM, and at a pH value between 2.0 and 9.0, e.g. at7.0. Furthermore, also pectines may be used as chelating agent forcadmium or other heavy metals.

The cocoa shells depleted in metal species as listed above may be driedat a temperature of 20 to 140° C. at atmospheric pressure, e.g. at 80 to130° C., for a period of time of 1 min to 24 h, to a final moisturecontent of <10 weight %, e.g. 1, 2, 3 or 5 weight %. Alternatively,reduced pressure or vacuum-drying at a temperature between 20 and 50°C., e.g. around 40° C., may be applied to the cocoa shells depleted inmetal species, in order to achieve a final moisture content of <10weight %, e.g. 1, 2, 3 or 5 weight %.

Subsequently, the dried cocoa shells may be ground to a final meanparticle size of less than 75 μm, which condition has to be fulfilled by99.5% of the particles according to measurements performed by a watersieving method. The maximum particle size may be adjusted, e.g. from 60to 200 μm. Grinding may be done by an impact classifier mill. The feedmaterial is conveyed through a pneumatic feed duct into the grindingzone. The main airflow enters the mill through the main air inletunderneath a grinding disc which rotates with tip speeds of 70 to 120m/s. Grinding fineness is adjusted by the speed of the classifier wheel.A product of the desired particle size is drawn through the classifier,whereas coarse material will be rejected for further size reduction.Resulting fines will be separated from the airflow in a cyclone filterunit downstream to the mill.

In another aspect, this invention covers food products containing driedand ground cocoa shells processed as described above. This cocoa shellpowder may be used as a low-germ food ingredient in dairy products orfor making cocoa-based products such as chocolate or chocolatecompositions, and for the manufacture of food products such as fillings,compounds and beverages containing up to 70 weight %, e.g. 5 to 40weight %, preferably 20 to 30 weight % of the processed cocoa shellpowder as replacer for non-fat cocoa solids. For example, cocoa powderor cocoa solids in confectionery such as chocolate or in food productscontaining chocolate compositions as bulk ingredient may be substitutedby the processed cocoa shell powder partly or completely. Possibleapplications may include chocolate fillings, cocoa beverages, ice cream,mousse, pralines, tablets, vending mixes, enrobing of biscuits or savorycrackers. Cocoa shells processed as described above may not only be usedas replacer for non-fat cocoa solids such as e.g. whipping agents inmousses or mouthfeel enhancers in vending mixes, but may also impartfunctional benefits by increasing viscosity, e.g. in ice cream, frozenfood or confectionery.

Furthermore, dried and ground cocoa shells processed as described abovemay be used to impart colouration in food products, including but notlimited to cocoa-based products.

Characteristics and features of cocoa shell powder as disclosed:

Taste and Flavour

-   Procedure: analyzed by taste panel-   Result: light cocoa with slight hints of cinnamon and nuts; taste    neutral and free from off-flavours (smoky, burnt, hammy, mouldy,    musty)

Colour

-   Procedure: Measurements of external colour took place with the aid    of spectrophotometer Minolta CM-3500d. The spectral reflectance of    the object was determined for the whole visible range of the    spectrum. The corresponding values L*, a* and b* were calculated    from the spectral reflectance data. In order to analyze the external    colour of cocoa shell powder, a 30 mm target mask was used. The    liquefied and homogenized cocoa shell sample was filled into a    petridish, until the layer reached a thickness of at least 3 mm.    After removing air bubbles, the petridish was heated in an oven    until the sample temperature was 40° C.±2° C. For colorimetric    measurements on alkalized cocoa shell powder, a white matrix    compound comprising 49.80 weight % sucrose, 22.70 weight % whey    powder, 26.90 weight % hydrogenated palm kernel stearin, 0.59 weight    % soya lecithin and 0.01 weight % natural vanilla flavour was used.    The colour values as listed in Table 1, Table 2 and Tables 6 to 13    refer to the CIE 1976 L*a*b* COLOR SPACE method developed by Minolta    Camera Co., Ltd. This measuring code closely represents human    sensitivity to colour. Equal distances in this system approximate    equally perceived colour differences, L* is the lightness variable    (0→Black; +100→White), whereas a* (−60→Green; +60→Red) and b*    (−60→Blue; +60→Yellow) are chromaticity coordinates.

TABLE 1 COCOA SHELLS ALKALISED WITH POTASSIUM COCOA Parameter CARBONATESHELLS NATURAL L* 11 16.9 a* 7.1 9.9 b 7.1 12.4

Table 1 demonstrates the impact of alkalization on colour variations ofnatural cocoa shells, covering a range of natural cocoa powder colour upto the colour of black alkalized cocoa powder.

TABLE 2 Parameter LOWER SPECIFICATION UPPER SPECIFICATION L* 2.7 4.7 a*1.0 2.0 b 0.5 1.5

Table 2 defines the lower and upper specification of L*a*b* values forreference black cocoa powder.

Microbiological Requirements

TABLE 3 Total Plate Count max. 5000 cfu/g ISO 4833 - 2003 Yeasts andmoulds both max. 50 cfu/g ISO 7954 - 1987 Enterobacteriaceae less than10 cfu/g ISO 21528-2 - 2004 E. coli Absent in 1 g ISO 7251 - 2005Salmonella sp. Absent in 750 g ISO 6579 - 2004 cfu: colony-forming unitsISO: International Organisation for Standardisation

Physical Requirements

TABLE 4 Fineness 75 micron (on Min. 99.5% IOCCC 38 - 1990 total product)IOCCC: International Office of Cocoa, Chocolate and Confectionery

Dependent on the degree of alkalization, the cocoa shell powderprocessed as claimed in this invention has bulk densities between 0.35kg/L (natural cocoa shell powder) and 0.52 kg/L (black alkalized cocoashell powder).

Composition Analysis

-   Parameters determined: JJL2G; JJL1Q; JJL3Q; JJF02; J3087; J8265;    A7273; A7274; J1048; J1045; J1046; J1038; J1050

TABLE 5 TEST RESULTS Physical-chemical Analysis JJL2G Water content (#)Method: §64 LFGB L 06.00-3, mod., Gravimetry Water content 4.8 g/100 gJJL1Q Raw protein (#) Method: §64 LFGB L 06.00-7, mod., Titrimetry (N ×6.25) Protein 16.1 g/100 g JJL3Q Protein corrected with theobromine &caffeine nitrogen (#) Method: calculated Protein 14.7 g JJF02 Fat total(#) Method: §64 LFGB L 06.00-6 mod., Gravimetry Fat. total 3.6 g/100 gJ3087 Fiber (total dietary) (#) Method: AOAC: 991.43/32.1.17 (2000),gravimetric Total dietary fibre 54.3% J8265 Caffeine and Theobromine (#)Method: §64 LFGB L 45.00-1, HPLC-DAD Theobromine 670 mg/100 g Caffeine74.7 mg/100 g A7273 Vitamin B1 - Thiamine base Method: EN 14122 2001mod., rp-HPLC-FLD Subcontracted to an Eurofins laboratory accredited forthis test. Vitamin B1 (thiamin) 0.271 mg/100 g A7274 Vitamin B2 -riboflavin Method: En 14152, mod., rp-HPLC-FLD Subcontracted to anEurofins laboratory accredited for this test. Vitamin B2 (riboflavin)0.130 mg/100 g J1048 Sodium (Na) Method: DIN EN ISO 11885, mod., ICP-OESSubcontracted to an Eurofins laboratory accredited for this test. Sodium(Na) 54 mg/kg J1045 Potassium (K) Method: DIN EN ISO 11885, mod.,ICP-OES Subcontracted to an Eurofins laboratory accredited for thistest. Potassium (K) 27000 mg/kg J1046 Magnesium (Mg) Method: DIN EN ISO11885, mod., ICP-OES Subcontracted to an Eurofins laboratory accreditedfor this test. Magnesium (g) 4400 mg/kg J1038 Calcium (Ca) Method: DINEN ISO 11885, mod., ICP-OES Subcontracted to an Eurofins laboratoryaccredited for this test. Calcium (Ca) 3000 mg/kg J1050 Phosphorus (P)Method: DIN EN ISO 11885, mod., ICP-OES Subcontracted to an Eurofinslaboratory accredited for this test. Phosphorus (P) 3400 mg/kg (#) =Eurofins Analytik GmbH, Wiertz-Eggert-Jörissen is accredited for thistest LFGB: Lebensmittel-und Futtermittelgesetzbuch (DE) AOAC:Association of Analytical Communities EN: Europäische Normen DIN:Deutsches Institut für Normung

Fat bloom is measured by visual evaluation on a scale between 0 and 5,in which 0 represents a perfect surface and 5 standing for an unpleasantcocoa product covered with white or grey layering on the surface.Replacing cocoa powder, i.e. non-fat cocoa solids, partly or completelyby the processed cocoa shell powder significantly improves the finalproduct's resistance to fat bloom. For example, a biscuit enrobed with achocolate product containing the processed cocoa shell powder as fatbloom inhibitor shows a resistance to fat bloom increased by 10% ascompared to biscuits enrobed with standard chocolate products. Withoutwishing to be bound to a specific mechanistic theory, the inventorsconsider a possible mechanism to lie in a reduced concentration of cocoabutter in cocoa shells, which itself leads to a reduced separation ofcocoa butter from the matrix of cocoa products.

Based on process steps comprising an optional microbial decontaminationof sieved cocoa shell particles, followed by washing and treating with achelating agent thereof, the invention as claimed provides a cocoa shellpowder characterized by a significant low microbial burden (see Table3). Furthermore, this cocoa shell powder processed as claimed in thisinvention finally contains less than 5 ppb of ochratoxin A, less than 4ppb of aflatoxins and less than 1 ppm of arsenic, cadmium or lead.Pesticides detectable are below Maximum Residue Levels (MRL) accordingto Regulation (EC) No 396/2005.

As regards hitherto known products, Moner Llacuna S.A. offers cocoafibers under the product name “Ficao”. Healy Group provides cocoa fibersfrom selected parts of cocoa husks.

The products of this invention demonstrate several advantages overhitherto known food products containing cocoa shells. Thus, the cocoashell powder of this invention:

-   -   can be economically produced on an industrial scale;    -   under toxicological aspects provides a safe replacer for cocoa        powder;    -   provides health benefits to cocoa-based products due to:        -   a reduced fat content of an average 2 to 6 weight %,        -   a reduced theobromine and caffeine content,        -   an increased dietary fiber content of about 54 weight %,        -   an increased dietary fiber content of about 60 weight %,        -   an increased flavanol content,        -   being enriched in potassium (K) (about 2.7 weight %), which            in connection with a low sodium (Na) content (about 0.005            weight %) considerably lowers blood pressure;    -   can be used to impart colouration in food products;    -   significantly increases the resistance of chocolate products to        fat bloom;    -   can be used to increase the resistance to fat bloom in compounds        which comprise the cocoa shell powder of the present invention;    -   improves rheological properties, e.g. by imparting an increase        in viscosity yield value for frozen confectionery coatings;    -   exhibits a high water-absorption capacity; and    -   provides a broad range of applicability;    -   can be used for improved “structure-building”, e.g. mousse,        compared to compositions without the cocoa shell powder of the        invention described herein;    -   can used as part of caseinate-free vending mixes which comprise        the cocoa shell powder of the invention described herein,        wherein said mixes provide improved mouthfeel compared to mixes        which do not comprise the cocoa shell powder of the present        invention;    -   can be used in compositions for improving barrier function, e.g.        cone-spraying, wherein said compositions comprise the cocoa        shell powder and wherein the compositions have improved barrier        function compared to compositions that do not comprise the cocoa        shell powder of the present invention;    -   can be used in paper, packaging material, and poster products        which comprise the cocoa shell powder of the present invention.

Following is a description by way of example only of processes andproducts of this invention.

Example 1. Processing of Cocoa Shell Powder, Including Washing and HeavyMetal Removal

-   -   Step 1: Crack preroasted cocoa beans    -   Step 2: Remove and separate cocoa shells from nibs    -   Step 3: Select the fraction of correct particle size (>1 mm) by        sieving    -   Step 4: Grind the selected and decontaminated fraction by a        centrifugal breaker    -   Step 5: Wash the ground fraction by an aqueous bicarbonate        buffer    -   Step 6: Alkalize the washed fraction by an aqueous solution of        potassium carbonate and sodium hydroxide    -   Step 7: Add an aqueous solution of citric acid as chelating        agent    -   Step 8: Dry the cocoa shells depleted in heavy metals at 100° C.        under atmospheric pressure    -   Step 9: Grind the dried cocoa shells by an impact classifier        mill

Alternatively, alkalization may also follow step 9, which comprises thegrinding of dried cocoa shells.

Example 2. Manufacturing of Black Cocoa Shell Powder Using an IronComponent

The reference alkalization procedure to produce black cocoa powder wasapplied to processed cocoa shells (see Example 1) in order to achieve asimilar blackness in cocoa shell powder as in reference black cocoapowder (see Table 2).

An amount of 7.5 kg of processed cocoa shells was heated to 95° C. and1.04 kg water were added. When the mixer jacket temperature reached 125°C., 0.1225 kg potassium carbonate in 0.1225 kg water as well as 0.066 kgiron(III)sulfate and 0.35 kg sodium hydroxide in 1.05 kg water wereadded. After a reaction time of 60 min, pressure was released and thealkalized cocoa shells were dried and ground before colour analysis.

Results:

1. Colorimetric Measurements on Pure Alkalized Cocoa Shell Powder

TABLE 6 REFERENCE BLACK COCOA BLACK COCOA SHELL Parameter POWDER POWDERL* 2.7-4.7 4.5 a* 1.0-2.0 0.7 b 0.5-1.5 1.0

Basically, the L*a*b* values for black cocoa shell powder are within thecolour specification as set for reference black cocoa powder. The slightdeviations as regards the a* parameter are not visually distinguishable.Therefore, black cocoa shell powder prepared in an alkalizing mediumcontaining an iron component may be used as replacer for black cocoapowder.

2. Colorimetric Measurements on Alkalized Cocoa Shell Powder Blended ina Matrix

TABLE 7 REFERENCE BLACK BLACK COCOA COCOA POWDER SHELL POWDER INParameter IN MATRIX (5 wt. %) MATRIX (5 wt. %) Difference L* 24.8 23.6−1.2 a* 6.4 4.2 −2.2 b 7.7 5.5 −2.2

TABLE 8 REFERENCE BLACK BLACK COCOA COCOA POWDER SHELL POWDER INParameter IN MATRIX (10 wt. %) MATRIX (10 wt. %) Difference L* 16.1 14.8−1.3 a* 6.0 3.5 −2.5 b 6.5 4.1 −2.4

TABLE 9 REFERENCE BLACK BLACK COCOA COCOA POWDER SHELL POWDER INParameter IN MATRIX (15 wt. %) MATRIX (15 wt. %) Difference L* 15.3 11.8−3.5 a* 4.2 2.9 −1.3 b 5.0 3.1 −1.9

For evaluation of internal colour, reference black cocoa powder andblack cocoa shell powder each were blended in a white matrix (seedetails on colour analysis) for final concentrations of 5, 10 and 15weight %, respectively. Doubling of the inclusion percentage of blackcocoa shell powder from 5 to 10 weight % resulted in 8.8 points lower L*values, i.e. more blackness, and trebling of the inclusion percentage ofblack cocoa shell powder from 5 to 15 weight % resulted in 11.8 pointsmore blackness. Comparatively, doubled and trebled inclusion percentagesfor reference black cocoa powder led to a decrease of L* values by 8.7and 9.5 points, respectively. Therefore, black cocoa shell powderimparts a dark colouration in food products more effectively thanreference black cocoa powder does.

Example 3. Manufacturing of Black Cocoa Shell Powder without an IronComponent

The reference alkalization procedure to produce black cocoa powder wasapplied to processed cocoa shells (see Example 1) in order to achieve asimilar blackness in cocoa shell powder as in reference black cocoapowder (see Table 2).

An amount of 7.5 kg of processed cocoa shells was heated to 95° C. and1.04 kg water were added. When the mixer jacket temperature reached 125°C., 0.1225 kg potassium carbonate in 0.1225 kg water as well as 0.35 kgsodium hydroxide in 1.05 kg water were added. After a reaction time of60 min, pressure was released and the alkalized cocoa shells were driedand ground before colour analysis.

Results:

1. Colorimetric Measurements on Pure Alkalized Cocoa Shell Powder

TABLE 10 REFERENCE BLACK COCOA BLACK COCOA SHELL Parameter POWDER POWDERL* 2.7-4.7 5.7 a* 1.0-2.0 2.5 b 0.5-1.5 1.6

The L*a*b* values for black cocoa shell powder are not within the colourspecification as set for reference black cocoa powder. However, thesedeviations are not visually distinguishable. Therefore, black cocoashell powder prepared in an alkalizing medium without an iron componentmay be used as replacer for black cocoa powder.

2. Colorimetric Measurements on Alkalized Cocoa Shell Powder Blended ina Matrix

TABLE 11 REFERENCE BLACK BLACK COCOA COCOA POWDER SHELL POWDER INParameter IN MATRIX (5 wt. %) MATRIX (5 wt. %) Difference L* 24.8 26.11.3 a* 6.4 6.8 0.4 b 7.7 8.2 0.5

TABLE 12 REFERENCE BLACK BLACK COCOA COCOA POWDER SHELL POWDER INParameter IN MATRIX (10 wt. %) MATRIX (10 wt. %) Difference L* 16.1 17.41.3 a* 6.0 6.0 0.0 b 6.5 6.4 −0.1

TABLE 13 REFERENCE BLACK BLACK COCOA COCOA POWDER SHELL POWDER INParameter IN MATRIX (15 wt. %) MATRIX (15 wt. %) Difference L* 15.3 15.1−0.2 a* 4.2 4.9 0.7 b 5.0 5.3 0.3

For evaluation of internal colour, reference black cocoa powder andblack cocoa shell powder each were blended in a white matrix (seedetails on colour analysis) for final concentrations of 5, 10 and 15weight %, respectively. Doubling of the inclusion percentage of blackcocoa shell powder from 5 to 10 weight % resulted in 8.7 points lower L*values, i.e. more blackness, and trebling of the inclusion percentage ofblack cocoa shell powder from 5 to 15 weight % resulted in 11.0 pointsmore blackness. Comparatively, doubled and trebled inclusion percentagesfor reference black cocoa powder led to a decrease of L* values by 8.7and 9.5 points, respectively. Therefore, black cocoa shell powderimparts a dark colouration in food products more effectively thanreference black cocoa powder does.

Example 4. Increased Resistance of Chocolate Products Containing CocoaShell Powder to Fat Bloom

-   -   Evaluation of trials: every 14 days    -   Total evaluation time: 1 year    -   Scorings: 0=high gloss    -   1=loss of gloss    -   3=fat bubbles visible    -   5=sample completely grey

TABLE 14 Fatbloom Evaluation Time Scoring: 0 days +14 days +1 month +1½month +2 months Sample 1 0 0 1 1 3 Sample 2 0 0 0 0 0

-   Sample 1: chocolate products based on cocoa powder-   Sample 2: chocolate products, wherein all cocoa powder has been    replaced by cocoa shell powder

Example 5: Use of Cocoa Shells in Cone Spraying Compound for ImprovedBarrier Function, Rheology and Shelf Life

Description

Compound coatings used for spraying ice cream cones have a fine textureand unique fat composition which are required for homogeneous spraying.In this context the rheology of the compound plays an important role inorder to obtain a layer of compound in the cone which is as thin aspossible. Another typical technical challenge is that the compound hasto guarantee a good humidity barrier in order to keep the cone crunchyand ensure the quality of the product until the end of the shelf life.The shelf life of these ice creams is generally 12 months.

Milk and dark compound coatings generally contain between 7.5 and 17.5%of cocoa powder to deliver the chocolate-like taste.

Purpose

The purpose of the trial is to evaluate the effect of 100% replacementof cocoa powder by fine cocoa shell powder in a compound coating on:

-   -   Rheology and quantity of compound in end application    -   Humidity barrier function in end application    -   Shelf life of end application

Material and Methods

The reference compound coating (REF) is a dark compound which contains9% cocoa powder in the recipe. The test compound coating (TEST) has thesame composition as REF except for the cocoa powder which is replaced100% by fine cocoa shell powder. As such TEST contains 9% of fine cocoashell powder.

Rheology

The rheology of the compound coating is measured with a rheometer.Measurement occurs at 40+/−0.1° C. in the test product. Viscosity isexpressed in mPa·s and yield value in Pa. Rheology is determined on bothcompound coatings REF and TEST.

Humidity Barrier Function

The water-test procedure gives an indication of water absorption of thebiscuit after spraying with the compound coating and gives an indicationon how well the spraying can act as barrier.

3 cones are taken per reference and weighed. Water (3° C.) is poured inthe cones up to 1 cm from the top of the cone. Let rest for 20′.

Then the weight of the cones after emptying is measured and the conesare left upside down for 1′.

Shelf Life

For the shelf life test, first all coated cones are filled with icecream and freezed for 1 hour. Then 2 sets of cones are made with eachset consisting of an equal number of cones REF and TEST.

An accelerated conservation test is performed in which 5 cones REF and 5cones TEST are put in the refrigerator at 5° C. for evaluation of shelflife. Evaluation of shelf life is done by a taste panel and is based onscoring crunchiness by a taste panel during 5 subsequent days.

A scoring system is used with:

0=crunchy

1=not crunchy

2=chewy

(11 cones REF and 11 cones TEST remain in the freezer for 1 year withmonthly evaluation of crunchiness for shelf life evaluation. (theseresults will be available only in January 2014; for the first 3 monthsthe score is 0 for both REF and TEST)

Results

Impact on Theology

Specification REF TEST Linear viscosity 150-350 202 218 (mPa · s) Cassonviscosity 144 163 (mPa · s) Yield value (mPa) <3 0.9 1.1

The use of fine cocoa shell powder results in a 8% and 13% increase inlinear and Casson viscosity, respectively. This indicates that thefluidity of the compound is slightly decreased and the internalrestriction is increased. The yield value is increased with 22% (from0.9 to 1.1 mPa) which may result in a more homogeneous spray coating.

Quantity of Compound in the Cone

Before and after spraying, the cones are weighed.

REF TEST Weight cone 16.060 16.440 before spraying (g) Weight of cone24.256 24.315 after spraying (g) Weight of 8.196 7.875 compound (g)

With the same settings for the spraying installation, there is 4% lesscompound on weight basis in the cone with TEST compared to REF.

Distance is defined as the length between the top of the cone biscuitand the horizontal layer where the compound triangle at the bottom (inthe tip) begins (See, FIG. 1)

REF TEST Distance (mm) 61.3 +/− 1.96 63.8 +/− 1.96

The tip at the bottom of the ice cream cone with TEST compound is 4%less high compared with the tip in the cone after spraying with the REFcompound. This result is in line with the lower total weight of compoundwith TEST compared with REF. These results can be explained by thechange in rheology (in particular of the yield value) when fine cocoashell powder is used in compound TEST.

Shelf Life (Accelerated Model)

T + 1 T + 2 T + 3 T + 4 REF 1 1 2 2 TEST 0 0 0 2

The evaluation of shelf life is done by a taste panel (n=4) and is basedon crunchiness scoring over 5 subsequent days (0=crunchy, 1=not crunchy,2=chewy). The ice cream cones which are kept in the refrigerator at 5°C. and are made with the fine cocoa shell powder in the coating (TEST)remain crunchy until day 3, while for the REF, the product loses itscrunchiness already from day 1 and is chewy as from day 3.

Barrier Function

WATER REF TEST Depth of the bottom/17 65.3 65 cone 1 with chocolate 24.224.2 cone 1 after water 25.3 24.4 weight of water 1.1 0.2 Depth of thebottom/18 61.7 62.5 cone 2 with chocolate 24.9 23.8 cone 2 after water26.1 24 weight of water 1.2 0.2 Depth of the bottom/19 62.5 65 cone 3with chocolate 24.7 23.8 cone 3 after water 25.4 24 weight of water 0.70.2

The average water absorption is 1.0 in REF and 0.2 in TEST. The waterabsorption is less when fine cocoa bran powder is used in comparisonwith cocoa powder.

The invention claimed is:
 1. A method of increasing resistance againstfat bloom in a cocoa-based product comprising a cocoa shell powder,wherein the cocoa shell powder is produced through the steps of:selecting and separating cocoa shells from nibs; drying the cocoashells, wherein the cocoa shell powder is characterized by the followingfeatures: (a) a mean particle size of less than 75 μm; (b) a finalmoisture content of ≤5 weight %; (c) a neutral taste or a light cocoaflavor with slight hints of cinnamon and nuts, free from off-flavours;(d) colour variations covering a range of natural cocoa powder colour upto the colour of black alkalized cocoa powder; (e) a dietary fibercontent of about 55 weight %; (f) a total microbiological plate count ofless than 5000 colony-forming units per gram; and (g) a bulk densitybetween 0.35 kg/L and 0.52 kg/L.
 2. A method according to claim 1,further comprising an alkalization step.
 3. A method according to claim1, further comprising the step of adding a chelating agent to the cocoashells.
 4. A method according to claim 3, wherein the chelating agent isdissolved in water and comprises an organic acid containing at least twocarboxylic groups or any alkali metal salt or alkali earth metal saltthereof.
 5. A method according to claim 1, wherein the selected cocoashell fraction is characterized by a mean particle size of more than 1mm.
 6. A method according to claim 1, wherein washing is performed byaqueous buffer solutions for a period of time between 1 min and 12 h ata pH value between 2.0 and 9.0 and at a temperature between 15° C. and100° C.
 7. A method according to claim 2, wherein alkalization isperformed by suspending cocoa shells in water and by adding analkalizing medium.
 8. A method according to claim 7, wherein thealkalizing medium optionally includes an iron component and comprises anaqueous solution of an alkali metal carbonate or an aqueous solution ofan alkali metal hydroxide or a mixture of alkaline solutions.
 9. Amethod according to claim 7, wherein the cocoa shells are alkalized fora period of time between 20 min and 85 min, at a temperature between 80°C. and 130° C., at a pressure between 2 bar and 8 bar, and wherein thealkalized cocoa shells are cooled to 60 to 70° C. in 7 to 12 min anddried for 35 to 85 min.
 10. A method according to claim 1, wherein thecocoa shell fraction is dried for a period of up to 24 h at atemperature above 50° C. at atmospheric pressure or at a temperaturebelow 50° C. under reduced pressure to a moisture content of less than10 weight %.
 11. A method according to claim 1, wherein the cocoa shellsare ground to a mean particle size of less than 75 μm.
 12. A methodaccording to claim 3, further comprising a step of grinding the cocoashells prior to adding the chelating agent.
 13. A method according toclaim 1, further comprising a step of grinding the cocoa shells afterthe drying step.
 14. A method of increasing resistance against fat bloomin a cocoa-based product, wherein the method comprises the steps of:cracking cocoa beans; removing and separating cocoa shells from nibs;selecting and separating a fraction of cocoa shells; grinding theselected fraction of cocoa shells; adding a chelating agent to the cocoashells; and drying the cocoa shells; grinding the dried cocoa shells;and adding the resulting cocoa shell powder to the cocoa-based product.